Individual compounds from the category of non-acylated bicyclic imidazo-3-amines and imidazo-5-amines which form the basis of the compounds according to the present invention are known to have interesting pharmacological properties. Thus, certain imidazo[1,2-a]pyridines are described as blood pressure-reducing active ingredients (GB-B-1,135,893), as anthelmintics and antimycotics (J. Med. Chem. 1972, 15, 982–985) and as anti-secretory active ingredients for the treatment of inflammatory diseases (EP-A-0 068 378). EP-A-0 266 890 and J. Med. Chem. 1987, 30, 2031–2046 also describe an effect of individual imidazopyridines against inflammatory diseases, in particular of the stomach. Further pharmacological effects described for individual representatives of the category of non-acylated imidazo-3-amines and imidazo-5-amines are antibacterial properties (Chem. Pharm. Bull. 1992, 40, 1170), antiviral properties (J. Med. Chem. 1998, 41 5108–5112) and the effect as benzodiazepine-receptor antagonist (J. Heterocyclic Chem. 1998, 35, 1205–1217).
Greater interest has been shown in the category of non-acylated bicyclic imidazo-3-amines and imidazo-5-amines in that multicomponent reactions which are suitable for automated combinational chemistry have been developed for the synthesis thereof. Whereas the isolated intermediate product continues reacting in the next step in conventional reaction sequences, equilibrium reactions take place between the educts and various intermediate products in multicomponent reactions, so a stable product is formed. The multicomponent reaction is particularly efficient if the desired product markedly predominates in the state of equilibrium, or is even removed from the equilibrium by irreversible reaction conditions. Ideally, it should also be possible to use as many variable and readily obtainable educts as possible in a multicomponent reaction which can be employed for combinational chemistry.
Thus, C. Blackburn et al., in Tetrahedron Lett. 1998, 39, 3635–3638, describe a three-component condensation for the parallel synthesis of bicyclic imidazo-3-amines and imidazo-5-amines. The synthesis publicized by K. Groebke et al., in Synlett 1998, 661–663 is similar to the synthesis in that reaction. H. Bienayme and K. Bouzid also describe a multicomponent reaction for the combinational synthesis of bicyclic imidazo-3-amines with which isolated imidazo-5-amines have also been produced in Angew. Chem. 1998, 110 (16), 2349–2352.
N-acylated bicyclic imidazo-3-amines were previously known only in so far as Chayer et al., in Tetrahedron Lett. 1998, 39, 9685–9688, describing salts of N-acylated imidazo[1,2-a]pyridines unsubstituted in the 3-position as intermediate stage in the production of the corresponding compounds C-acylated in the 3-position.
Furthermore, only N-acylation at the amino nitrogen is described for individual bicyclic imidazo-3-amines produced by solid phase synthesis (Blackburn in Tetrahedron Lett. 1998, 39, 5469–5472).